CIS Guru Question
 

Could someone please explain a few things regarding 78-83 US and ROW CIS parts usage.

1. Did Porsche use different metering plate assemblies for U.S. and Euro?
Or, did they use the same one for all these years?

2. Did Porsche use different Fuel Distributors between the U.S. and Euro in 78-79 and on thru 83? Has anyone figured out the part numbers?

I searched Pelican's PET but didn't find part #s on the metering plates, and I've been told conflicting info on the FD.

Why I'm asking:

I started with a U.S. 81' 3.0 engine. My goal was to get as close to a 78-79 Euro motor as my budget would alow. I changed out the stock runners/airbox with the large (78-79) ones. I ported the heads to match. The fuel distributor was a xxx.031 (I believe is from a 78-79) the W.U.R. is a xxx.045 which should be a match.

The car runs very strong at this point but is leaning out as the RPM's increase. I'm thinking that the metering plate (stock 81') is not right unless they are all the same.

Thanks in advance for any information,
Paul

Not a Guru here but I have heard from a respected P-car mechanic that CIS motors have a tendency to go lean in the higher RPMs.

How do you know it is going lean? I am no expert, but I have a '81 ROW that I have recently done a head stud replacement. In the process of tearing it down, I went through the parts to learn more about the motor that I have. What I found is that, contradictory to BA and Wayne's books, all ROW cars had 39mm intakes and ports. Since your US car is an '81, you should have 9.3:1 compression. I would say you need to try and replicate a 930/10 motor, i.e. a '81-83 ROW, not a 78-79 ROW... or at least somewhere in between (looking at compression ratios). Have you thought about adjusted the cam timing? As I understand it, the cam timing, higher compression, and 39mm runners and ports all contribute to the extra 24 hp. You are mostly there with the 9.3:1 CR and 39mm ports. Adjust the cam timing and you should be getting a little better top end power.

Back to your specific questions 1 and 2. I am sure the FD is different between the '81-on cars, but I can't remember if it is for 78-79. I think so. I have my CIS off of the car and would be happy to verify any part numbers to compare with yours.

Bosch Fuel Distributor Application.....
 

Never been a CIS Guru but starting to understand the principle......These data were taken from the Bosch Parts Application Table and might be of help.

Fuel Distributor------Application --------- Notes

0-438-100-010------- '76 - '77 ------------ 3.0 liter Carrera (Euro)

0-438-100-031------- '78 - '79 ------------ SC

0-438-100-031------- '80 ----------------- SC (until June '80)

0-438-100-097------- '80 ----------------- SC (July '80 on ward)

0-438-100-097------- '81 - '83 ------------ SC

Not exactly sure but it might be also applicable to '78 Euro (if any). Hope these help some readers. Thanks.

Tony

Not sure if they really do, this is my 80' on the dyno

http://forums.pelicanparts.com/uploa...1193524129.jpg

Just confirmed my 81 ROW fuel distributor to be a 097, if that helps any.

Tony, I think the last three digits on a '81-'83 U.S.-version fuel distributor should be 077.

Brian

Ben,

Don't forget to check the Bosch number on the airflow sensor housing on your '81 RoW engine, and pass that on as well.

Also, you should find that the Warm Up Regulator will have the part number xxx.089.

Are these Euro numbers?
Bosch USA states that the US '80-'83 SC's have 0 438 100 077 fuel distributor; the '78-'79 have 0 438 100 031.

Paul:
The WUR and FD match for a US '78-'79 CIS.
Since you ported the heads on the '81 heads to 39mm, I suggest that you time the cams to 0.9 - 1.1 mm.
That will match your '78-'79 CIS and give you some extra HP with the 9.3 : 1 CR.
The cam timing on a US '81 engine is 1.4 - 1.7 mm.
You may also consider re-curving the distributor; the '81 distributor is too advanced in mid-range RPM.

Very cool guys.

"Air Flow Sensor" This is the name I was looking for. This houses the "Metering Plate."
Part numbers for the different (IF DIFFERENT) Air Flow Sensors, is what I'm looking for.

Bobboloo: I have heard that too so I checked before beating up the motor on the track.
MunsonBW: First ran it unloaded on a smog machine and got very lean #s.
I then ran it again (not completely warm) loaded (wheels on dyno) and got this:
HC: 126,
CO: 0.13
CO2: 12.90,
NOX: 435
02: 2.70
@ 3 - 4 Grand RPM's

I did this just before closing last night next door at the smog shop so just a quickie.

I guess the better way of stating my intentions would be:
I have an 81 U.S., I had the Euro/larger runners/airbox, the F.D. x.031 and the W.U.R. x.045
I ported the heads to match the runners. I believe they are 37mm but you may be right on that and the 9.3:1 compression.

My concern is that the lean condition is coming from the possiblity of the "Air Flow Sensor", or "Metering Plate", or the geomitry inside the part is different from the 78-79 and the 81 that I have. i.e. bigger throats, plates, ratio of plate movement to F.D. plunger/rod movement.

Thanks and YES, what are you F.D. and W.U.R. numbers? The wur # is a little hard to see so don't go nuts for me.


Boyt911sc:
Thanks for the parts #s. I'm trying to determine if 78-79 EURO used the .031 as the U.S. Model. I have been told 2 different things.

1. Euro used the .031 in 77-83 and U.S. only used in 78-79 then switched to the .097.
2. Euro used an exclusive F.D. (part # unknown at this time) for the 77 - ?? (83 im guesing)

It's this "unknown" F.D. that is suppose to be very rare and no one really knows about it.
ANY ONE, Bueler, Bueler....

ScotR:
Thanks for the #'s
My guy next door does not have the dyno capability on his smog machine. SUCKS!

1982911SCTarga:
This backs up my theory on the "EURO" using .031 77-83 and the U.S. switching to the .097 in 80.

Jim Williams:
Yes, numbers, numbers, numbers. I don't have my numbers (yet) off my air flow meter. But, will next time I'm in there.
Also, I want to research the .089 F.D. in Porsche's PET.


Thanks all for replying.

Paul
P.S. I WILL get a pic of the engine and post ASAP.

Gunter...

Posted same time as yours. GLAD to hear from you. I was hoping you would jump in. Thanks for your past help and the car is still running very strong.

Cams timed when I was building. Spot On the #s there.

Check my last post.
I'm off to San Diego to spend the night the Air Craft Carrier with the kids. So, I'll check back tomorrow.

Thanks everyone
Paul

HI Paul
some thing for the weekend for you to translate, could be of some use to you ?????

http://forums.pelicanparts.com/uploa...1194720082.jpg

I was afraid that I was going to have to get the number off the plate itself... but found the number on the housing.

Air metering housing = 0438 120 143
WUR = 0438 140

Jim, this doesn't jive with what you were expecting. I'll have to dig tonight and see what this means. I just took a lunch break from being arms deep in a rebuild of the engine.

and the rest,

http://forums.pelicanparts.com/uploa...1194720203.jpg

http://forums.pelicanparts.com/uploa...1194720236.jpg

the photo is not to good on the one below and the righting also, if you think it could be of any use let me know and I will see if I can make a better copy.

http://forums.pelicanparts.com/uploa...1194720318.jpg

http://forums.pelicanparts.com/uploa...1194720501.jpg

http://forums.pelicanparts.com/uploa...1194720537.jpg

regards mike

MBEngineering
Are these Euro numbers? This supports that the F.D. was the same on 78-79US and Euro.

Is that what I'm seeing?

Paul

MBEngineering

I posted before your second post showed up. WOW! Yes indeed time to translate.

Anyone Sprecezy Duoich?

Paul

HI Paul
I hope thay are , as I am quite a way from you and I work on "EURO" cars most days(7).
if you need any more info , let me know .

regards mike

Me thinks:

Mengenteiler = FD
Luftmengenmesser = Airflow Sensor housing
Warmlaufregler = WUR
Bosch Kennzeichen = Bosch numbers

Most of those numbers look like Euro

Gunter,

The data were taken from a Bosch Application for 911 (specific to engine designation). The info I furnished are very similar to MBEngineering's data. The CIS components for my '78 Targa (US version) are the same as specified in the Bosch Application Table (the table includes FD, CSV, WUR, AAV, fuel injectors. fuel pump, etc.).

Please refer to MBE's info and it will show a column for early & late SC's FD as -031 and -097 respectively. Same as the Bosch Table.

Tony

Just to clarify:
We have to differentiate between Euro and US.
My info about US models comes from Boschusa; I have no info on Euros.
If you have a US '78 Targa, Boschusa states that your FD should be 0 438 100 031 like you said.
But the FD for US '80-'83, according to Boschusa, should be 0 438 100 077.

I have several complete US CIS systems: '78, '80, '82 and the numbers from Boschusa correspond to the actual numbers on my 3 CIS systems.

Well I am fairly satisfied that the .031 F.D. was used on the 78-79 US and Euro.

Anyone disagree???

Now for the air flow meter.

If I haven't mentioned it lately.... THIS BOARD ROCKS!!!!!! You guys are the best!

Ben,

The number in your post for the WUR is an incomplete number. There will be three more digits stamped into the WUR body: 0438 140 xxx. This sometimes requires a very close look to make out the last 3 digits.

Gunter,

The reference Bosch table I used does not tell me whether US or RoW car. So your info should be the right one unless someone has other idea. Thanks.

Tony

Ok here it all is for a '81 ROW car. 39mm ports and runners:
Air metering housing = 0438 120 143
WUR = 0438 140 089
FD xxx xxx 097

Since we have the attention of the CIS gurus, any idea what this is? ~80mm long with a 5-7mm rubber plug on the end. It was laying on the back of my CIS airbox. Amazing it hasn't been lost yet.


http://forums.pelicanparts.com/uploa...1194735253.jpg

Ben,

That fits into the hole in the airflow sensor housing through which you access the mixture setting for the Fuel Distributor. It doesn't really do much except to keep to keep trash out of the allen adjuster. It is a small miracle it is still with the engine.

Wunderbar.
Ben: Bosch used that plug for all their K-Jetronic FD's; like Porsche, Volvo etc.
I like the plug and to make sure it doesn't get lost, I have a short small key chain trough the eye and around one of the fuel lines.
A little Vaseline helps to get it in. :rolleyes:

[QUOTE=Pkaaso;3580586]Well I am fairly satisfied that the .031 F.D. was used on the 78-79 US and Euro.
QUOTE]

Paul:
Unless you go with larger P/C's and a higher lift cam like a 964, you are maxed out with your set-up.
The US FD for '78-'79 (Non-Lambda) is good for slightly better delivery but a bored-out throttle body is additional cost/work for no real gain.
I suggest that you make the best of what you have; SSI's will add about 10-15 HP depending on muffler.
Concentrate on recurving your distributor, Steve Weiner will do it.

Two years ago I bought an '82 SC engine and build a SS 3.2 with '78 CIS.
98mm P/C's, 964 cam, Ported heads to 39mm to mate with the larger runners from the '78 CIS.
With the SSI's, I added about 40 horses to the stock 180 HP.
I use a '78 ignition distributor.
Cost was about $5k

Gunter
I an running the WEB Cams, 21/20 seems to have a very smooth / even power band.

So, the Luftmengenmusser (air flow meter/throttle body) is the debate.

Using the chart from MBEngineering (thank you very much for the contribution)
I understand this would be ROW/Euro part numbers.

78 - 81 used 0438 120 070
81 - 82 used 0438 120 143

Question:
1.What is the difference? i.e. size of bores, geomitry of mechanism, etc...?
2. Did the US and ROW use the same parts year for year?
3. Is there another year/model's "Air Flow Meter" that may function more favorably?

I will check what I have but I suspect is will be the x.143

BTW The Aircraft Carrier (now museum) "Midway" was an incredable experience. We slept in the enlisted man's bunks. SMALL, SMALL, SMALL. Ate the mess chow and toured the ship, did flight simulators and got to see 1940's engineering. Ship completed in 1945, was built in 18 months by huge number of the ladies, and lunched the most sorties in Desert Shield amoung the 4 other newer Air Craft Carriers in the gulf at that time. Retired in 92'. WONDERFUL Experience.

Thanks All,
Paul

So, the air flow meter I have on my 81' is 0 438 120 149
This should be the U.S. one correct for the year.

*MB*,
Any chance you could get the column that shows the "Air Flow Meter" Eruo part numbers, please?

*boyt911sc* Maybe you have the U.S. numbers for the air flow?

Anyone else have the part numbers for the U.S. "Air Flow Meters?" I'd like to comare with the Euro.

I also have a U.S. 74' that has 0 438 120 004 air flow meter. But I can't find the throtle body numbers.

Anyone know where the throttle body numbers are?

Thanks,
Paul

Can any one tell me why the Euro SC with 9.8 C/R made less power than the Euro C3 with 8.5 C/R?

Are there differences in these two CIS components?

I believe it was due to cam timing issues and other such "tuning" factors. I read about it recently, but my memory is fading on this issue.

I was just at Paul's shop and he's getting a big lean-out above 4,000 RPM. His fuel pressures are good, so the idea is that the Air Flow Meter he currently has isn't properly calibrated to the amount of air coming into the engine at higher revs and isn't commanding the FD to meter enough fuel in (that's the basic theory, anyway).

So, all ideas are still welcome guys.

Paul,

The reference table that I have does not tell me whether it's US or EURO. The AFMS for '74 is -004 and for '81-'83 is -149 from this Bosch Reference table same as you have. I would suggest that you PM Gunter for this info.

Tony

Boy911sc,
Thanks for the info.

What number does it give you for the 78-79 U.S. AFMS.

To be clear, Paul:
Do you have a complete US '78 CIS sitting on top of an '81 US 3.0 liter engine?
What is the cam timing on the 20/21?
Carbs would get you richer at higher RPM's.
Knowing that the CIS leans out at higher RPM's, I keep my US '78 CIS mixture on the rich side.
I cannot see how a slightly larger bored throttle body would get you a richer mixture at higher RPM's.
Forget about the '74 AFM

No Gunter, not a complete system.

I have the 81' that I replaced the following:

1. runners/airbox with 78-79 large (heads ported to match)
2. FD with the .031
3. WUR .045

Cam timing: 1.9 - 2mm.
I have the CO mixture set fairly rich at idle.

I'm not implying that the larger throttle body would richen the top end. I think problem is the AFM. I may have an extra 78-79 AFM (if I can find it) that I will install and test again on the smog dyno.

Thanks,
Paul

O.K.

Gunter,
Yes, I am calling the metering plate housing the AFM (Air Flow Meter) because I have heard the term serveral here. The newer cars call them AFM or Air Mass Sensors.

I haven't found the other 79' CIS system yet. It's lost in Jon's garage (450knotoffice) can attest to this nightmare of a parts heaven.

I am still hoping someone can enlighten me on the diffence of the AFM's.

I will call WEB cams tomorrow and ask. The 2mm was recomended from a long time builder but we did not set for the cam especially.

Thanks,
Paul

Hi Mike at MBE,

Would it be possible for you to post a photo of the right hand side of your chart that has the heading "911.911S 2,7 l Hub..."?

Paul,

I have some data from measurements I made on an '80 US air flow meter (AFM) and an '80 RoW AFM.

The US one, an xxx.118 has a 76 mm plate, and the RoW, an xxx.070, has an 80 mm plate. There are also some differences in the venturi contours. I will post sketches of the venturies when I can draw them out and scan them. I thought this might have some bearing on your mixture problems.

Ben,

Can you make some measurements on your xxx.143 AFM (I used a vernier caliper to make mine), including the sensor plate, and post them? I will plan on posting all this info on my website when I get it together.